Physics Lecture Review: Mechanics, Waves, and Thermodynamics

Vocabulary flashcards generated from lecture notes covering key topics in rotational motion, universal gravitation, simple harmonic motion, acoustics, fluid mechanics, and thermodynamics.

Moment of Inertia

A measure of an object's resistance to changes in its rotational motion relative to a specified axis of rotation, which decreases when mass is brought closer to the axis.

Angular Acceleration

The rotational physical quantity that directly describes how quickly the speed of rotation changes over time.

Lever Arm Application

The principle of applying a force as far away from the hinges or pivot point as possible to maximize torque and make an object rotate easily.

Torque and Moment of Inertia Relationship

Under identical net torque, an object with a smaller moment of inertia experiences a greater angular acceleration according to $\text{Angular Acceleration} = \frac{\text{Net Torque}}{\text{Moment of Inertia}}$.

Static Equilibrium

The physical condition of a completely stationary object in which both the net external force and the net external torque acting on it are equal to zero.

Rotational Kinematics

The branch of mechanics that describes rotational motion by recording angular position, angular velocity, and angular acceleration without analyzing applied forces or torques.

Work Done by Torque

The physical quantity describing the energy transferred to an object as a result of an applied torque causing rotation through an angle.

Rotational Kinetic Energy

The energy stored in a body purely as a result of its continuous rotational motion about an axis without translational movement.

Angular Momentum

The physical quantity representing the rotational analog of linear momentum possessed by a spinning object.

Inverse-Square Gravitational Relationship

The law stating that doubling the separation distance between two massive bodies decreases the gravitational force of attraction between them to one-fourth ($\frac{1}{4}$) of its original value.

Gravitational Field

The region of space surrounding any object with mass that exerts an attractive force on other masses.

Gravitational Potential Energy

The energy stored in an object due to its elevated position within Earth's or another body's gravitational field.

Escape Velocity

The minimum launch speed required for an unpowered body to permanently break free from a planet's gravitational attraction.

Orbit

A continuous, gravity-bound curved trajectory around a celestial body where forward motion is continuously balanced by gravitational pull.

Kepler's Laws of Planetary Motion

The physical principles governing orbital behavior, including the rule that a line drawn from a star to a planet sweeps out equal amounts of area during equal intervals of time.

Periodic Motion

A type of motion that continuously repeats along a fixed path at equal, regular time intervals.

Physical Pendulum

An extended, rigid body hanging from a fixed axis near its top end that swings back and forth in an oscillatory pattern around a non-central pivot.

Damped Oscillation

Oscillatory motion where energy is continuously dissipated, causing the maximum displacement or amplitude of successive swings to decrease until coming to rest.

Longitudinal Sinusoidal Wave

A wave in which localized medium elements move parallel to the wave propagation direction with position displaced over time according to a smooth sine function.

Compression

The high-density phase of a longitudinal wave propagation where particles in the medium are tightly packed together.

Wave Intensity

The rate of wave energy transfer per unit time passing through a unit surface area perpendicular to the direction of wave propagation.

Beats

Rhythmic variations in loudness produced by the interference of two overlapping sound waves of slightly different frequencies, such as $440\,\text{Hz}$ and $442\,\text{Hz}$.

Nodes

Specific stationary points along a standing wave pattern where the amplitude of vibrational motion remains constantly zero.

Doppler Effect

The physical phenomenon causing an observed shift toward a higher perceived pitch or frequency when a wave source approaches a stationary observer.

Specific Gravity

A dimensionless unit ratio comparing the density of a substance to the density of pure water at $4\,^\text{o}\text{C}$.

Pressure

The physical quantity measuring the perpendicular force applied per unit area, expressed as $P = \frac{F}{A}$.

Pascal's Principle

The physical law stating that a pressure change applied to an enclosed fluid is transmitted equally and undiminished to every portion of the fluid and container.

Archimedes' Principle

The physical law establishing that the upward buoyant force acting on a submerged object is exactly equal to the weight of the fluid displaced by that object.

Bernoulli's Principle

The fluid dynamics principle stating that an increase in the flow speed of a fluid within a horizontal section results in a decrease in its internal pressure.

Zeroth Law of Thermodynamics

The law establishing that if two systems are each in thermal equilibrium with a third system, they are in thermal equilibrium with each other.

Microscopic Thermal Expansion Mechanism

The thermal process where constituent particles gain kinetic energy, causing their average equilibrium separation distance to increase.

Temperature Gradient

The driving temperature difference that determines the spontaneous direction of thermal energy transfer between bodies in contact.

Heat Energy Exchange

The physical quantity directly measured by tracking temperature variations inside a sealed, insulated calorimeter.

Radiation

The heat transfer mechanism that transports thermal energy through electromagnetic waves without requiring any physical medium.

Ideal Gas Law Pressure Behavior

The behavior derived from $PV = nRT$ showing that doubling the absolute temperature of a gas inside a rigid, fixed-volume container causes its pressure to double.

Internal Energy of an Ideal Gas

The physical property of an ideal gas sealed in a rigid container that directly increases as a result of a temperature rise.

Work Done During Constant-Pressure Heating

The extra thermal energy required by a gas expanding at constant pressure compared to a fixed volume, because some absorbed energy performs work on the surroundings.

Thermodynamic System

A specifically chosen macro-region of the physical universe selected for thermodynamic study, separated from its surroundings by physical or theoretical boundaries.

Work Done During Volume Change

The mechanical energy transferred to surroundings when an expanding gas pushes against external pressure, changing the volume of its container.

First Law of Thermodynamics

The principle asserting that the change in internal energy of a system equals the net heat added to the system minus the work done by the system: $\Delta U = Q - W$.

Adiabatic Process

A thermodynamic process in which energy is exchanged strictly as work, with no heat entering or leaving the system ($Q = 0$).

Heat Engine

A thermodynamic system that continuously absorbs heat from a high-temperature reservoir, converts part of it to mechanical work, and expels waste heat to a low-temperature reservoir.

Engine Cycle

A recurring sequence of thermodynamic processes that repeatedly returns a working fluid back to its initial state to continuously generate work.

Entropy

A fundamental thermodynamic property that directly quantifies the degree of microscopic disorder and randomness within a system.

Second Law of Thermodynamics

The principle dictating that heat spontaneously flows from hotter to colder bodies and that the total entropy of an isolated system always increases.

Irreversible Process

A real-world thermodynamic process that dissipates energy through friction or non-equilibrium steps and cannot return both system and surroundings to their initial states.

Carnot Cycle

An idealized theoretical cycle composed of two reversible isothermal processes and two reversible adiabatic processes that achieves maximum theoretical thermodynamic efficiency.

Enthalpy

A thermodynamic state property defined as the sum of a system's internal energy and the product of its pressure and volume: $H = U + PV$.